Google assistant skip missing type

homeassistant/components/google_assistant/smart_home.py

@@ -141,6 +141,13 @@ async def sync_serialize(self):
         if not traits:
             return None
 
+        device_type = get_google_type(domain,
+                                      device_class)
+
+        # If no device type found, skip
+        if not device_type:
+            return None
+
         device = {
             'id': state.entity_id,
             'name': {
@@ -149,7 +156,7 @@ async def sync_serialize(self):
             'attributes': {},
             'traits': [trait.name for trait in traits],
             'willReportState': False,
-            'type': get_google_type(domain, device_class),
+            'type': device_type,
         }
 
         # use aliases

tests/components/google_assistant/test_smart_home.py

@@ -14,6 +14,7 @@
     const, trait, helpers, smart_home as sh,
     EVENT_COMMAND_RECEIVED, EVENT_QUERY_RECEIVED, EVENT_SYNC_RECEIVED)
 from homeassistant.components.demo.light import DemoLight
+from homeassistant.components.demo.binary_sensor import DemoBinarySensor
 from homeassistant.components.demo.switch import DemoSwitch
 
 from homeassistant.helpers import device_registry
@@ -558,6 +559,37 @@ async def test_empty_name_doesnt_sync(hass):
     }
 
 
+async def test_missing_device_type_doesnt_sync(hass):
+    """Test that an entity without device class and no default doesn't sync."""
+    light = DemoBinarySensor(
+        'Demo Sensor',
+        state=False,
+        device_class='dummy_class'
+    )
+    light.hass = hass
+    light.entity_id = 'binary_sensor.demo_sensor'
+    await light.async_update_ha_state()
+
+    with patch('homeassistant.components.google_assistant.'
+               'trait.OpenCloseTrait.supported', return_value=True):
+        result = await sh.async_handle_message(
+            hass, BASIC_CONFIG, 'test-agent',
+            {
+                "requestId": REQ_ID,
+                "inputs": [{
+                    "intent": "action.devices.SYNC"
+                }]
+            })
+
+    assert result == {
+        'requestId': REQ_ID,
+        'payload': {
+            'agentUserId': 'test-agent',
+            'devices': []
+        }
+    }
+
+
 @pytest.mark.parametrize("device_class,google_type", [
     ('non_existing_class', 'action.devices.types.SWITCH'),
     ('switch', 'action.devices.types.SWITCH'),